With veterinary practices returning to the “new norm”, veterinary professionals around the UK are being urged to highlight the benefits of feline blood pressure checks among cat owners whose pets are seven years of age and older (Taylor et al., 2017).
The Mercury Challenge
This move follows the launch of the results of Ceva’s Mercury Challenge, the largest international feline hypertension study which encouraged vet practices around Europe to take blood pressure measurements from over 10,000 cats, 4,000 of which were from the UK (Ceva, 2020).
The study showed that more than 40 percent of cats enrolled in the Mercury Challenge were hypertensive, with a blood pressure about 30 percent higher than the blood pressure value found in normotensive cats. This high percentage suggests that feline hypertension may be even more common than suspected, especially in the ageing cat population with the mean age of hypertensive cats found to be 13 years old. The risk was shown to increase as cats age or if cats have other conditions such as chronic kidney disease (CKD), with one in three cats found to have both conditions during the challenge, or hyperthyroidism.
Known as the “silent killer”, hypertension often develops insidiously without any early signs. Unfortunately, when clinical signs occur it is often too late and consequences can be dramatic: the eyes, kidneys, heart and brain can be severely affected.
Blood pressure clinics
Utilising both staff and facilities as efficiently and cost-effectively as possible and changing clients’ perception of preventative healthcare means that veterinary nurses are well placed to become increasingly involved in preventative care clinics and owner education, which can contribute to optimal clinical care. Here we take a look at the steps that can be taken in practice to help identify hypertensive cats.
Step one: agree on a practice policy
As it is important that everyone in the practice is “singing from the same hymn sheet”, as the idiom goes, and following the same practice policy on feline hypertension, your first step in setting up a clinic should be to agree on a practice policy. Therefore, it is advisable that the whole practice team – from receptionists to vets – is aware, and educated, about the benefits of early identification and high-risk cat profiles. High-risk, or target, felines include cats that are seven years of age or over, cats with associated diseases such as CKD or hyperthyroidism and those with target organ damage.
It is also important to consider a policy regarding how and when your clinic might run. Hypertension clinics can be run at specific times or during consultations and can be free of charge or charged at a set rate, and nurses can play an essential role in the routine measurement of blood pressure to help identify hypertensive cats. These are some things to consider when outlining your practice policy for feline blood pressure clinics.
Step two: spread the word
It is essential that you are spreading the word to clients in order to get sufficient footfall to your new clinic to make a difference. You might do this by utilising waiting-room decor and ensuring that literature and visual cues are placed around the practice (eg hypertension hints in reception, waiting room posters, wall displays and target cat stickers). Social media posts on feline hypertension will help raise awareness of the condition; other client communication tools could include practice-to-cat-owner emails and information on feline hypertension in the client newsletter. Animal health companies have a range of marketing material which can help you spread the word on feline hypertension.
Step three: identify target cats
Your next step should be proactively identifying at-risk individuals. Veterinary professionals can check feline patient records to see if they are a target cat. These cats can then be identified if they are in the cat ward or prep room, during consultations, during non-emergency phone enquiries and when clients are booking consultations for their cats. Proactive outreach could include searching practice management software for age and risk conditions and contacting owners by phone, text message or email or through their vaccination reminder.
Step four: prepare consult room
Studies have shown that allowing for acclimatisation and a quiet, undisturbed room will reduce the magnitude of situational hypertension to less than 20mmHg in cats (Brown et al., 2007). Therefore, preparing the right setting for your clinic is essential and the consultation room set-up must be carefully considered.
Prepare the room by ensuring all equipment is ready for use, and take steps to minimise the risk of interruptions. Help the cat acclimatise to the room by allowing them to explore for 5 to 10 minutes when they enter. While the cat is exploring, it is a good time to take a detailed history with the owner. When ready, place the cuff and allow the cat to acclimatise to it before inflating. Once the cat seems comfortable, record its resting position, the site of the cuff and the cuff size so that you can be consistent for future measurements. Take a series of five to seven blood pressure readings, discard the first reading and then take an average of the other results.
Step five: diagnose and treat
An early diagnosis is crucial to prevent serious damage. However, once diagnosed, hypertension can be easily and efficiently treated with the daily administration of an appropriate anti-hypertensive treatment such as amlodipine.
Top tips for reliable readings
Sarah Caney, an RCVS recognised feline medicine specialist, has recorded her top tips for reliable readings which are discussed in this final section of the article.
Firstly, you should use a quiet room for measuring blood pressure, one that is away from barking dogs and general practice noises such as telephones and human traffic. Minimise the time that the cat spends in the waiting room if possible as this often increases stress levels in cats. A suggestion for this might be to advise the owner to keep the cat in the car with them until the room is free and you are ready.
Consider advising the pre-visit use of gabapentin (off licence) in cats that get very stressed by clinic visits and/or blood pressure (BP) measurements. Sarah typically recommends that owners give their cats a 20mg/kg dose of gabapentin orally two hours before putting their cat into their carrier for transport to the clinic (van Haaften et al., 2017).
Once in the room, Sarah recommends always measuring the patient’s blood pressure before doing any additional assessments on the cat. If this is not possible, she suggests adding a 30-minute rest period after any other necessary procedures before measuring blood pressure. You should also take your time and use minimal restraint when handling the cat and taking measurements. Consider the use of headphones so that the cat is unaware of any noise relating to the procedure.
For Doppler BP measurements there is no need to clip the fur even in long-haired cats, suggests Sarah, as using clippers may be stressful to the cat. Instead, prepare the area by wiping with surgical alcohol, then apply plenty of ultrasound gel and use a sphygmomanometer for Doppler BP measurements that allows slow and gradual cuff deflation. You should then slowly inflate the cuff in a series of gentle puffs, as sharp inflations can surprise or stress the cat. Sometimes doing a series of “practice” cuff inflations and deflations can be helpful in acclimatising the patient to the procedure. Furthermore, you should completely deflate the cuff between readings for Doppler BP measurements, otherwise the procedure may start to become uncomfortable and, therefore, stressful to the cat.
Collect at least five readings, but discard the first reading if it is very different to the others before averaging the remaining readings. If the readings are very variable, continue to collect readings until they plateau and average the plateau readings. If no plateau is reached, the lowest reading is likely to be the most representative of the cat’s true systolic BP.
Always record the cuff size used and site of BP measurement, states Sarah, as size of cuff and location will affect the readings obtained. The cuff should be level with the right atrium; if lower than this, the reading will be higher than the “true” BP. The ideal cuff width is 30 to 40 percent of the limb or tail circumference. If wider than this, the readings obtained will be lower than the “true” BP.
Lastly, you should discard cuffs that inflate unevenly or need securing with tape to stop them “popping off”.